//https://leetcode.cn/problems/reverse-string/


class Solution {
public:
    void reverseString(vector<char>& s) {
        std::reverse(s.begin(),s.end());   
    }
};


class Solution {
public:
    void reverseString(vector<char>& s) {
        int n = s.size();
        for (int left = 0, right = n - 1; left < right; ++left, --right) {
            swap(s[left], s[right]);
        }
    }
};